1. Field of the Invention
This invention relates to filters for use with aquariums inside of the aquarium, as opposed to filters which are exterior to the aquarium, or mounted to the inside wall of the aquarium. In particular, the present invention is directed to an aquarium filter which has an improved filtering and aeration efficiency while maintaining simplicity and convenience of operation. It also functions as a multiple use system since its readily adaptable design allows for the addition of optional capabilities with peripheral aquarium devices, chemical filtering and pre-filtering.
2. Description of the Prior Art
The numerous filtering systems for today's aquariums include exterior filters and interior filters. Of the interior filters there are floating (suspended), bottom and wall-mounted designs. In the aforementioned, the bottom filter is the most similar to the present invention. These bottom filters are described in U.S. Pat. Nos. 2,782,161; 3,477,580; 4,186,093; 4,620,924; 4,753,723; and 4,842,726. These bottom filters are composed of several compartments which serve a distinct purpose. There is generally a compartment in which the contaminated fluid enters and passes through a filtering medium into a clean fluid chamber. It is then dispersed by source of air which creates an air lift, lifting the decontaminated fluid through a lift tube or chamber and back in to the aquarium.
There are several drawbacks to these systems. First, in large tanks or with high gas flow rates, these filters have a tendency to float, disturbing the hydrodynamic environment and occasionally dismembering the unit, thus introducing additional contaminants. The common construction of the filters including several enclosed compartments requires painstaking labor with brushes to fit into various crevices and corners. In addition to the man-made chemical and/or mechanical filtering system, a biological filtration system resulting from the growth of microorganisms in the non-chemical filtering material is established by the natural environment of the aquarium. Thus, when these filters are cleaned and the filtering material is replaced, the result is the destruction of the biological filtration system which is very critical to the health of optimal water conditions. There is also a problem with many interior aquarium filters wherein small or baby fish can become trapped in the water intake slots.
A critical design criterion which has restricted existing filters is flow rate limitation. This flow restriction bounds the aeration and filtering capabilities of aquarium filters, therefore in larger aquariums, additional filters are needed which take up valuable tank space. Some filter designs have attempted to improve flow rates by reconfiguration of the individual components responsible for fluid intake, filtering or expulsion. All three of these components must be sized and configured as a single unit to prevent flow constriction by another portion of the filter, thus incapacitating improvements to individual filter components.
Accordingly, while the prior art bottom aquarium filters are utilized successfully, further improvements are warranted to alleviate the aforementioned problems.